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A relativistic quantum theory of gravity 
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#19
Jul2707, 11:39 PM

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thank you for your support. You are right, virtual photons of QED are methaphorical nonobservable concepts. The entire theory can be recast in the actionatadistance form without losing the accuracy of its predictions. This is done in a systematic way in E.V. Stefanovich "Relativistic quantum dynamics", http://www.arxiv.org/physics/0504062 which is based on the "dressed" (or "clothed") particle approach first proposed in O. W. Greenberg, S. S. Schweber, "Clothed particle operators in simple models of quantum field theory", Nuovo Cim. 8 (1958), 378 and developed further by L. D. Faddeev, M. I. Shirokov, and few others. Eugene. 


#20
Jul2707, 11:43 PM

Sci Advisor
P: 1,941

the interaction. E.g: phi^4 QFT has no mediating particle but we can still calculate scattering amplitudes. However, the phi^4 interaction remains local, whereas Eugene's proposed interaction is nonlocal. gravitons and gravitywaves are still a bit controversial. If they are unambiguously discovered, Eugene's theory will be in trouble and/or require modification. 


#21
Jul2807, 12:49 AM

P: 1,746

M. Kramer, et al. "Tests of general relativity from timing the double pulsar" http://www.arxiv.org/astroph/0609417 You are right, if graviton radiation is indeed discovered, this would mean a mild (but manageable) trouble for my theory. There would be no need to change the present (instantaneous) potential form of massmass and massphoton interactions. The theory could be fixed by adding extra terms to the Hamiltonian. These terms would describe the graviton emission and absorption. In the lowest order they might have the form a*a*aag + a*a*g*aa where a*/a are creation/annihilation operators of massive particles and g*/g are creation/annihilation operators of gravitons. This form of the Hamiltonian would be quite similar to the QED Hamiltonian in the "dressed particle" approach discussed in my previous post. Eugene. 


#22
Jul2907, 01:14 AM

P: 1,480

The binary pulsar decay may be a case of experimenters finding what they want to find. The problem I have with all force field communications is that there is no model of how forces can be connected this way  if a photon is emitted it travels by a well defined relationship with the properties of free space  it leaves here and it goes there  and it impacts and transfers momentum  in a field, something starts at A, travels to B  but it is still at A
Force fields cannot be imagined as particles going from A to B, yet most modern physics mathamatically models these fields the same way as light  I think Eugene's approach is a step in a direction that could lead to a holistic viewpoint of force fields in general I am curious whether Van Flanderen published a response to Carlip's paper? 


#23
Jul2907, 02:02 AM

P: 1,746

T. Van Flandern, J. P. Vigier, "Experimental repeal of the speed limit for gravitational, electromagnetic, and quantum field interactions", Found. Phys. 32 (2002), 1031. where he discusses Carlip's response. In my opinion, the debate Van Flandern  Carlip is in a dead end. Van Flandern basically says (rephrased): "there is no aberration in gravitational interaction, i.e., the force of gravity points to the instantaneous position of the source, not to the retarded position. Therefore, the propagation of gravity must be instantaneous" Carlip replies (rephrased): "Yes, there is no aberration of gravity (this is an experimental fact), but this doesn't prove the instantaneous propagation of gravity. In GR, if you take into account velocity dependent terms of higher orders in [itex] c^{2} [/itex], then, due to some lucky compensation, the total force does not have aberration, even though all terms are retarded." I think that Carlip is right. Aberration does not necessarily implies the superluminal propagation of the force. So, one cannot decide one way or the other by looking only at aberration. You are probably aware of Fomalont and Kopeikin recent measurements of the light deflection by Jupiter. They claimed that they have measured the speed of gravity that coincided with c. There is a lot of responses to this result (some references are in my paper), which argue that the speed of light was actually measured, rather than the speed of gravity. I am lacking deep knowledge of GR, so I can't appreciate the arguments in this debate. I was thinking about calculating this effect within my theory. This should be a good independent check of its validity. What do you think? Eugene. 


#24
Jul3107, 01:11 AM

P: 1,480

Yes  I am aware of the Kopeikin claim  and also the criticisms thereof.
If you can come up with numbers, critics take notice. I do not have your article in front of me at present  have you included a critique of Einstein's explanation of the perihelion precession of Mercury's orbit. I have read some criticism of how he used this to validate the c velocity of gravitational propagation  I need to reread your paper on this. In any event  you are in for an uphill battle. Had not realized the binary pulser data got a Nobel  I would say premature. Feynman got one too  as he said: "For sweeping the infinities under the rug" One of the problems in handing out such awards is that it blesses the work with an air of infallibility There are several issues that arise in connection with G fields  one is how fast the new position of an object is communicated to other masses when it moves, or when it accelerates or when the accelertion changes. Another is, if a particle is destroyed  how fast is this information communicated. These may each involve different kinds of propagation mechanisms. Then there is the interesting question of what is the nature of the de Broglie wave when matter is accelerated. Think how boring physics would be if all the problems were solved. How lucky we are to be able to ponder these questions. 


#25
Jul3107, 03:02 AM

P: 1,746

Hi, Yogi,
Nevertheless, I believe that GR is built on wrong physical premises (the 4D spacetime manifold) and sooner or later this will show up in disagreements with experiments. For example, I discuss possible violations of the equivalence principle in section 5.1. In 1993 Taylor and Hulse received the Nobel prize for the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation. This was a remarkable piece of work, and I wouldn't say that the prize was premature. Likewise, the development of the renormalized QED in the late 1940's was probably the greatest advance in theoretical physics after formulation of quantum mechanics in 1926. Of course, this doesn't mean that the final judgement has been pronounced on these matters. Eugene. 


#26
Jul3107, 09:45 AM

P: 361

Hello Eugene:
The Lorentz transformations are part of the machinery that characterizes the Lorentz group. That group is not approximate. It is the group that every observation ever made in regards to special relativity is based. If you decide to ditch the Lorentz group, well, you are not going to have friends. Superluminal propagation of interactions does create problems for causality. There are plenty of reasons not to like tachyon theory. doug 


#27
Jul3107, 01:09 PM

P: 1,746

Hello doug,
Lorentz group is a 6parameter group of transformations between inertial observers (it includes rotations and boosts). It is a subgroup of the full 10parameter Poincare group of inertial transformations, which, in addition, includes space and time translations. The Poincare group is an exact set of relationships. Any physical system, interacting or otherwise, must be invariant with respect to Poincare group transformations. We agree 100% about that. In quantum mechanics, this means that the Hilbert space of any physical system should carry an unitary representation of the (universal covering of the) Poincare group. Lorentz transformations are certain formulas that connect spacetime coordinates of events in different moving reference frames. For example, if observer O sees and event at point x at time t, then, according to Lorentz transformations, observer O' moving relative to O with velocity v sees the same event at the spacetime point (x', t'), where [tex] x' = (x vt)(1v^2/c^2)^{1/2} [/tex]..........(1) [tex] t' = (t  xv/c^2)(1v^2/c^2)^{1/2} [/tex]......(2) I prefer a slightly different notation in which velocity v is replaced by rapidity [itex] \theta [/itex], such that [itex] v = c \tanh \theta [/itex]. Then [tex] x' = x \cosh \theta  ct \sinh \theta [/tex].........(1') [tex] t' = t \cosh \theta  x/c \sinh \theta [/tex]........(2') My point is that transformations (1)(2) or (1')(2') do not follow immediately from properties of the Lorentz (or Poincare group). Some additional assumptions should be made to make such a derivation, and these are crucial assumptions. For example, one situation in which Lorentz transformations (1)(2) can be rigorously proven is when particles (whose worldline points and collisions form the events in question) are noninteracting. However, transformations of spacetime coordinates of such events become different from simple formulas (1)(2) if interaction between particles is turned on. I briefly discuss this point in section 5.2 of the paper. A more detailed discussion can be found in section 10.2 of http://www.arxiv.org/physics/0504062. The difference between the concepts of relativistic invariance (the Lorentz and Poincare groups) and manifest covariance (Lorentz transformations) has been known for a long time. I strongly recommend this paper D. G. Currie, T. F. Jordan, E. C. G. Sudarshan, "Relativistic invariance and Hamiltonian theories of interacting particles", Rev. Mod. Phys., 35 (1963), 350 where these two concepts are discussed with outmost clarity. In particular, the authors prove an interesting theorem which says that in a relativistic theory of classical particles their worldlines can transform by Lorentz formulas (1)(2) only if interaction is absent. The problems with causality arise if one applies Lorentz transformations (1)(2) (which are strictly valid for noninteracting systems only) to an interacting system. If one properly takes into account the interactiondependence of boost transformations, then these problems disappear. I briefly discuss this point in section 5.3 of the paper. A more detailed discussion can be found in section 10.2 of http://www.arxiv.org/physics/0504062. Eugene. 


#28
Jul3107, 05:13 PM

P: 1,480

"In 1993 Taylor and Hulse received the Nobel prize for the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation."
As I understand the results, they were very close to the desired fit on only one pulsar pair  maybe there are more recent tests. If your action at a distance theory is correct, there is no justification for gravitational waves. But of course you are already aware of that. "....the development of the renormalized QED in the late 1940's was probably the greatest advance in theoretical physics after formulation of quantum mechanics in 1926. Of course, this doesn't mean that the final judgement has been pronounced on these matters." It gives very close correlation to the measured values  but It is ad hoc from the standpoiint of a physical explanation. With regard to the Lorentz tranforms cited by sweetser  I have yet to see an experiment that establishes the truth of those parts of the transforms that are the result of the one way velocity of light  what is proven is the invarience of the interval  but this is easily obtained from Minkowski unification which leads to the result that the two way velocity is constant. Selleri spend most of his later years reviewing the known experiments dealing with SR time dilations and concluded they could all be easily explained with simple inertial transforms without reference to the xv/c^2 term that arises from the one way constancy postulate. While LorentzEinstein transforms may be correct, there needs to be a distinguishing experiment one that invalidates either Selleri or Einstein. I raise this because it bears on the issue of synchronization and consequently causality ...when information travels faster than light, the causalty issue does not occur in Selleri transforms. 


#29
Jul3107, 06:18 PM

P: 1,746

M. Kramer et al. "Tests of general relativity from timing the double pulsar", http://www.arxiv.org/astroph/0609417 Briefly, I think the trouble began already in the original formulation of QED (late 1920's). The Hamiltonian of this theory was derived from vague analogies with Maxwell's electrodynamics, and this Hamiltonian didn't satisfy some very important physical principles (the stability of vacuum and 1particle states). This Hamiltonian was useless for Smatrix calculations beyond the leading perturbation order, because of infinities. Tomonaga, Schwinger, and Feynman fixed a part of this problem in the late 1940's. They added infinite counterterms to the original Hamiltonian in such a way that all infinities in the Smatrix canceled out and very precise agreement with experiment could be achieved. However, as you said, they "swept infinities under the rug". This rug was the Hamiltonian. In renormalized QED, the Hamiltonian has infinite terms, so it is useless for anything but Smatrix calculations. Another improvement of QED is needed in order to obtain both reasonable Hamiltonian and accurate Smatrix. This can be done by using the "dressed particle" approach. This approach has been known for a long time O. W. Greenberg, S. S. Schweber, "Clothed particle operators in simple models of quantum field theory", Nuovo Cim., 8 (1958), 378. Unfortunately, it didn't get much traction in modern quantum field theories. ADDED: Perhaps the most important idea that I had in my works is that there can be no unique and universal formula for boost transformations of particle observables (such as the formula for Lorentz transformations). Boost transformations should depend on the system in which these transformations are measured and on interactions acting in the system. That's why I am sceptical about attempts to find a universal transfrormation. Thanks. Eugene. 


#30
Jul3107, 11:57 PM

P: 1,480

Hi Eugene  from your post 23:
"No, I don't discuss or criticize Einstein's general relativity in the paper. I also believe that predictions made in GR are perfectly consistent within this approach. This theory made a huge number of correct predictions without any fitting parameters. This is truly amazing! And this makes so much harder to come up with an alternative theory." I recalled that you had derived the perihelion motion  so I pulled up your article and reread that part  you have treated this and found your derivation consistent with the observations  that is a big plus. I guess my only suggestion would be to deemphasize the action at distance premise since you have alternatives. But you raise a good point in that, while there is slowing of binary systems,  it doesn't mean necessarily that it takes the form of gravitational radiation  for all we know it the energy may be absorbed in some form of dark matter My own view is consistent with GR in part  in that masses condition space  they do not act directly upon one another. As you probably know, there are several authors including Sciama, that have developed theories to explain inertia in terms of Mach's principle  all such theories require instant action at a distance  so you might want to read some of these if you have not already done so. I will send you a link to one of Selleri's articles. Selleri is not accepted by main stream, nor as you know, is Van Flanderen. Selleri however, has a list of accomplishments a mile long, so he can't be ignored summarily 


#31
Aug107, 12:57 AM

P: 1,746

Yes, I used a fairly simple instantaneous potential SunMercury, which consisted of the usual Newtonian part plus small velocitydependent correction. The important part was to make sure that this potential satisfies the principle of relativistic invariance (commutation relations of the Poincare Lie algebra). Otherwise, it was simply fitted to reproduce the observed shift of the Mercury's perihelion. I want to emphasise that I didn't formulate this interaction from some first principles, and then found that the calculated perihelion precession agrees with measurements. Not at all. That would be a really great accomplishment, and I don't claim that. What I have done in this paper is, simply, a proof of principle. I wanted to show that one can, in principle, find an instantaneous gravitational potential, which satisfies all requirements that I formulated in the beginning of the paper (relativistic invariance, unitarity, agreement with experiment, etc.). In fact, I believe, that one can write many different potentials that would satisfy all these requirements. Currently, I have no idea what additional fundamental principles are needed, which would select just one true potential. My primary objective was to break the monopoly of GR on explanation of experimental facts. I wanted to show that there is a much wider class of acceptable theories, which agree with existing observations. It is even more important that some of these theories are perfectly compatible with quantum mechanics, which is not true for GR. Thank you. Eugene. 


#32
Aug307, 12:58 AM

P: 1,480

Eugene  try this link oldserver.ba.infn.it/~selleri/  10k
Articles R39 and R27 should be of some interest. If That Link doesn't work, you can google Franco Selleri and get a lot of his papers Would be interested in your opinion on the inertial transforms  Yogi 


#33
Aug307, 01:01 AM

P: 1,480

Just checking  looks like that link is incomplete  i will try to get it right



#34
Aug307, 02:26 AM

P: 1,746

thank you for the link to Selleri's papers. I read the paper R39 F. Selleri, "Recovering the Lorentz Ether", Apeiron 11 (2004), 246 where he proposes "inertial transformations" that are supposed to replace "Lorentz transformations" of special relativity. I have quite a few objections to different statements in this paper. I'll mention just two objections, which look the most obvious to me: 1. His "inertial transformations" imply that the velocity of light should depend on the velocity of the light source. I remember seeing experimental works in which this dependence was investigated directly. If I remember correctly, they measured the velocity of gamma quanta emitted by fast moving particles. In agreement with special relativity, no dependence on the particles' velocity was found. I don't have exact references to these papers. I'll try to find them tomorrow. 2. Selleri is right that it is difficult to measure Lorentz transformations for the time and position of events in direct experiments. However, it is much easier to measure their cousins  Lorentz transformations for the momentumenergy of relativistic particles. These transformations have been observed in numerous particle experiments, and they form a foundation for relativistic particle kinematics established with great precision. I haven't noticed any discussion of "inertial transformations" for momentumenergy in the Selleri's paper. However, I suspect, that his version of such transformations would be also different from the specialrelativistic experimentally established version. Regards. Eugene. ADDED: Reading his other paper R27: "Bell's spaceships and special relativity" didn't change my opinion. 


#35
Aug307, 03:02 PM

P: 1,746

T. Alvager, F. J. M. Farley, J. Kjellman, I. Wallin, "Test of the second postulate of special relativity in the GeV region", Phys. Lett. 12 (1964), 260. They directly measured (using the "time of flight" method) the velocity of gamma quanta emitted in decays of relativistic [itex] \pi_0 [/itex] particles. I can also recommend a good website with lots of references to experimental tests of special relativity http://math.ucr.edu/home/baez/physic...periments.html Eugene. 


#36
Aug307, 08:55 PM

P: 1,480

Can you direct me to the paragraph or words which you have relied upon to arrive at the above criticism? Regards Yogi 


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